In construction, such as new construction of homes or outbuildings like garages, sheds and the like, it is the common practice to provide a concrete floor slab. To secure the framing for walls, bolts are set into and cast into the slab when the slab is poured at the perimeter of the slab as dictated by the building plans. Often the bolt pattern is not aligned and the bolt sizes are different as per prevailing building codes, architect's plans or dictates from the structural engineer.
A plate, often a 2×4 or 2×6 or 3×4 or 3×6 piece of lumber defining a plate is secured over the bolts to provide a substrate for attachment of sills, wall framework and the like. Holes are drilled in the plate so that it may be placed over the bolts with the bolts passing through the allotted holes. Nuts are then threaded over the bolts to tie the plate to the slab. Since the bolts may not be aligned and of different sizes, the carpenter must measure each bolt size and measure where to place each hole in the plate to pass the bolt pattern.
One prior art device and method to make the position measurement, is illustrated in FIGS. 1-4. As shown in FIG. 1, there is a poured slab 10 having along and edge thereof a pattern of bolts 12 (only one shown in FIG. 1) which extend inboard of the edge of the slab. The bolts 12 are arranged along a line however during placement and the pouring of the slab 19 may not be aligned along a straight line. Further the bolts 12 may be of different diameters such that the pattern and size of the holes cannot be accurately predicted. Thus it is required to empirically mark and drill holes in the plate 14 so that the plate 14 may be mounted over the bolts 12 and tightened, with nuts, down to the slab 10.
To mark a plate 14 for the drill holes, straight lines 15a, b are marked on the slab 10 on either side of the line of bolts 12 using for example a chalk line. The lines 15a, b define the projected margins for the plate 14 to span and be passed over the bolts 12. The plate 14 (e.g. a 2×4) is then positioned with one edge along chalk line 15b. A marker 16 having a foot 18 and upstanding handle 20 is placed to position a first end 22 of the foot against the bolt 12 as suggested in FIG. 1.
The marker 16, according to the prior art, is shown in FIGS. 2-4. The foot 18 has a first end 22 and a second end 24. At each of the first and second ends 22, 24 there is an arcuate notch 26 to mate with the bolt 12. The foot 18 is generally flat having a length of about 9 inches and has upstanding walls 28 to enable the standing carpenter to use his foot to position the marker 16. Offset and upstanding from the foot 18 is a hollow handle 20. The handle 20 is 3½ inches from the first end 22 and 5 ½ inches from the second end 24. Since the notch 26 receives approximately half the diameter of the bolt 12, the handle 20 would be 3 and 5 inches, respectively, from the center of bolts 12 received in the notches 26. Disposed within the hollow handle 16 for axial movement is a plunger 30 having at one end a grip 32 and at the other end a pointed tip 34 (FIGS. 1 and 4) configured to impart a mark on the plate 14.
To mark the plate 14, the plate 14 is positioned along the chalk line 15b adjacent the bolts 12 as shown in FIG. 1. It is assumed in FIG. 1 that the plate is a 2×4. The marker 16 is positioned, with the tip 34 withdrawn into the handle 16, to mate the first end 22 with the bolt 12. In this position the plunger tip 34 is disposed approximately 3 inches from the center of the bolt 12 and aligned with approximately the center of the 2×4 plate 14. Holding the handle 16, the carpenter strikes the grip 32 with a hammer to drive the plunger 30 causing the tip 34 to mark the plate 14. In a similar fashion the carpenter moves down the bolt line marking locations on the plate 14. The carpenter then notes the diameter of the bolts 12 for each mark and drills the holes. The plate 14 is then position over the bolts 12 passing the bolts 12. Nuts (not shown) are threaded over the bolts to secure the plate 14 to the slab 10.
If the plate 14 were a 2×6, the carpenter would use the second end 24 thus positioning the tip 34 to be located near the center of the plate 14.
A drawback of the prior art device described above, is that it can only approximate the position on the plate since it is not adapted to handle a wide variety of bolt sizes. The notches 26 are of the same diameter and thus may not be suitable for bolt sizes ranging from ½ inches to 1¼ inches. For particularly large bolt sizes the prior art marker described above may be inappropriate.
Another drawback is that the carpenter must hold the grip to draw the plunger and tip into the handle thus making one hand operation almost impossible.
There is a need for an improved plate marker which is adapted to overcome the drawbacks noted above.